A genetic epidemiology study of congenital adrenal hyperplasia in Italy.

Congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21OHD-CAH) is an autosomal recessive disorder affecting steroidogenesis, due to mutations in CYP21A2 (6p21.3). 21OHD-CAH neonatal screening is based on 17-hydroxyprogesterone (17OHP) serum levels, showing high type I error rate and low sensitivity to mild CAH forms. Here, we used an epidemiological approach, which estimates the allelic frequency (q) of an autosomal recessive disorder using the proportion of homozygous patients, the mutational spectrum and the inbreeding coefficient in a sample of affected individuals. We applied this approach to 2 independent Italian cohorts of patients with both clinical and molecular diagnosis of 21OHD-CAH from mainland Italy (N = 240) and Sardinia (N = 53). We inferred q estimates of 2.87% and 1.83%, corresponding to a prevalence of 1/1214 and 1/2986, respectively. CYP21A2 mutational spectra were quite discrepant between the 2 cohorts, with V281L representing 74% of all the mutations detected in Sardinia vs 37% in mainland Italy. These findings provide an updated fine-grained picture of 21OHD-CAH genetic epidemiology in Italy and suggest the need for a screening approach suitable to the detection of the largest number of clinically significant forms of CAH.

A peculiar family with recurrent self-limited epileptic syndrome and associated developmental disorders in six girls.

We describe a complex family with two couples (two sisters who married two brothers) with consistent social and neuropsychiatric problems, originally from Sardinia. Each couple had three daughters, which shared electroclinical epileptic syndrome and developmental disorders. All patients suffered from mild to moderate intellectual disability, speech difficulties and behavioural disorders. Four out of six patients had epilepsy onset between 3 and 4 years of age. The epileptic history almost reflected the typical clinical course of a self-Limited Focal Epilepsy of Childhood. However, our patients don't have the complete features characteristic of one of the four specific self-Limited Focal Epilepsies of Childhood; a progressive evolution into a Developmental and/or Epileptic Encephalopathy with spike-wave activation in sleep was observed in the two older sister of the first family, which developed more severe developmental disorder too. In the other epileptic patients, improvement of EEG pattern was not coincident with an improvement of the developmental disorders. Brain MRI, performed in three patients, showed normal findings. Genetic analysis carried out so far (SNP-array, study of Runs of homozygosity, FMR1 triplet-repeat primer-PCR assay, Next Generation Sequencing based gene panel for epilepsy and neurodevelopmental disorders and Exome Sequencing), did not provide useful elements for an aetiological diagnosis.

Cognition in multiple sclerosis: Between cognitive reserve and brain volume.

BACKGROUND: Several correlations between cognitive impairment (CI), radiologic markers and cognitive reserve (CR) have been documented in MS. OBIECTIVE: To evaluate correlation between CI and brain volume (BV) considering CR as possibile mitigating factor. METHODS: 195 relapsing MS patients underwent a neuropsychological assessment using BICAMS. BV was estimated using SIENAX to obtain normalized volume of brain (NBV), white matter (NWV), gray matter (NGV) and cortical gray matter (CGV). CR was estimated using a previously validated tool. RESULTS: Pearson test showed a correlation between the symbol digit modality test (SDMT) score and NBV (r=0.38; p<0.000) NGV(r=0.31; p<0.000), CGV (r=0.35; p<0.000) and CRI score(r=0.42; p<0.000). Linear regression (dependent variable:SDMT) showed a relationship with CR scores (p=0.000) and NGV(p<0.000). A difference was detected between cognitive impaired and preserved patients regarding mean of NBV(p=0.002), NGV(p=0.007), CGV(p=0.002) and CR Scores (p=0.007). Anova showed a association between the presence of CI (dependent variable) and the interaction term CRIQ × CGV (p=0.004) whit adjustment for age and disability evaluated by EDSS. CONCLUSIONS: Our study shows a correlation between cognition and BV, in particular gray matter volume. Cognitive reserve is also confirmed as an important element playing a role in the complex interaction to determine the cognitive functions in MS.

Nomifensine: diagnostic test in hyperprolactinemic states.

Nomifensine, an antidepressant agent which activates dopamine (D) neurotransmission mainly by inhibiting DA reuptake in the central nervous system, was administered either to puerperal lactating women or to subjects with nonpuerperal hyperprolactinemia. In 10 postpartum women and in 7 women with no evidence of PRL-secreting tumor, oral administration of nomifensine (100 or 200 mg, respectively) induced in the following 5 h a clear-cut inhibition of plasma PRL levels; in 10 patients with PRL-secreting tumors, the drug did not lower plasma PRL levels. In 2 of these patients nonsupressibility of plasma PRL levels to nomifensine was the only indication of the existence of a pituitary microadenoma. It is proposed that acute nomifensine testing may be a valid neuropharmacological tool for discriminating between individuals with and without pituitary adenoma.

Rat tyrosine hydroxylase gene polymorphisms.

The rat tyrosine hydroxylase gene (TH) from a panel of outbred and inbred rat strains has been analysed by Southern blotting, restriction-endonuclease mapping and direct sequencing of PCR-amplified products for detecting DNA polymorphisms. Five polymorphic sites have been characterized. This information may be used in pharmacogenetic studies to determine the influence of the TH gene in animal models of affective disorders and addictive behaviours.

Molecular analysis of atypical beta-thalassemia heterozygotes.

This paper reviews the molecular pathology of a heterogeneous group of beta-thalassemia heterozygotes which may be referred to as atypical beta-thalassemia. This group includes four different categories of heterozygous beta-thalassemia, which are characterized, respectively, by (1) normal MCV and MCH; (2) normal Hb A2; (3) normal MCV, MCH, and Hb A2 and imbalanced globin chain synthesis only or, (4) the presence of clinical manifestations. The first group is represented by a limited proportion of double heterozygotes for alpha- and beta-thalassemia. The second group includes two categories. One category is double heterozygotes for delta- and beta-thalassemia with the delta-thalassemia mutation in cis or in trans to beta-thalassemia. A number of delta-thalassemia mutations which produce this phenotype by interacting with beta-thalassemia have been described. The other category within the second group is heterozygotes for some mild beta(+)-thalassemia mutations. Within the third group, conclusive evidence for a mutation within the beta-globin gene cluster producing the silent beta-thalassemia phenotype has been obtained solely for a C----T substitution at -101 within the CACCC box of the beta-globin gene. Possible candidates are the complex rearrangements (-T, +ATA; -T, +ATATA) found at position -530 from the cap site. In the group of thalassemic hemoglobinopathies, a series of mutations mostly located in the third exon and producing elongated or truncated molecules have been recently reported. Most of the mutations are silent at the protein level, produce inclusion bodies in peripheral erythrocytes, and show a dominant transmission pattern or occur sporadically.

Gestational diabetes: clinical characteristics and birth weight.

This retrospective study investigates the clinical characteristics of gestational diabetes mellitus (GDM) (time of diagnosis, different treatment, metabolic parameters, etc.) in relation to prepregnancy body mass index (BMI) and the influence of BMI on neonatal outcome. 93 GDM women and 110 control subjects were divided into three groups in relation to their prepregnancy BMI: normalweight (Nw), overweight (Ow) and obese (Ob). GDM was diagnosed significantly (p < 0.01) earlier in Ow and Ob than in Nw. Preterm deliveries and cesarean sections resulted significantly (p < 0.01) increased in all BMI categories of GDM respect to matched controls. Prevalence of neonatal macrosomia was higher in GDM patients (44.6%) compared with normal controls (15.4%) and correlated (p < 0.01) with prepregnancy BMI in both groups. Nevertheless in each BMI category the prevalence of macrosomia was significantly higher in GDM patients. The body weight increase during pregnancy was not associated with neonatal macrosomia. This study shows that prepregnancy BMI is an important risk factor for GDM and is predictive for macrosomia specially in women suffering from GDM.

Evaluation of the central dopaminergic activity in gestational hyperprolactinaemia by means of the electroretinographic technique.

Electroretinography, a simple, bloodless technique commonly used in ophthalmological diagnostic practice, seems to give important informations on the level of activity of the retinal and/or other central dopaminergic systems. The Authors have employed this technique in a group of 30 normal pregnant women in the ninth month of gestation, in order to evaluate the dopaminergic activity in a condition of physiological hyperprolactinemia, such as pregnancy, and in a group of 25 normal nonpregnant control women. The b wave amplitude of the electroretinographic traces was significantly higher in pregnant women than in controls, suggesting an over-activity of dopaminergic systems in late pregnancy. The possible interpretations of these data are discussed.

Dilemmas in intrauterine fetal growth retardation. The significance of anticomplement and heparin-like activities of placenta at term and the prognostic value of HCS and E3 maternal plasma concentrations during pregnancy.

The Authors studied the behaviour of anticomplement and heparin-like activities in human term placentas in relation to intrauterine fetal growth retardation. These two biological activities might be involved in regulatory mechanisms of great importance for the fetal growth. The anticomplement activity was significantly lower in IUGR placentas than in controls, while no change was found in heparin-like activity. The decrease of anticomplement activity might be associated to immunological mechanisms, possibly related to a placental microcirculation damage, with consequent fetal growth retardation. For what concerns HCS and E3 plasma levels during pregnancy, a significant reduction of HCS in IUGR subjects was observed, confirming a decreased functional activity of placenta. The E3 levels, on the contrary, were slightly, but not significantly lower in IUGR patients.

Molecular pathology and detection of beta-thalassemias.

In this review, we have described the molecular bases accounting for beta, delta beta and gamma delta beta-thalassemias, discussed the molecular mechanisms responsible for the production of mild forms of thalassemia and presented a strategy for detecting beta-thalassemia mutations in each at risk population. The molecular bases of beta-thalassemia are very heterogeneous. The great majority of beta-thalassemias are caused by point mutations affecting the coding region or critical areas of the beta-globin gene and are only rarely produced by gross gene rearrangements. By contrast delta beta and gamma delta beta-thalassemias most commonly result from gross gene deletion. Determinants recognized to date as able to produce mild forms of beta-thalassemias, are beta-thalassemia mutations with a high residual output of beta-globin chain production, coinheritance of alpha-thalassemia or nondeletion HPFH linked or not linked to the beta-globin gene cluster, delta beta thalassemias and specific beta-globin haplotype. Because in each population a restricted number of molecular defect occurs, strategies have been developed to detect the beta-thalassemia mutations in prospective parents in each at risk population. These strategies are based on the direct detection of the mutation by dot blot analysis on enzymatically amplified DNA using a limited number of oligonucleotide probes complementary to the most common mutations in each population.

Illegitimate recombination produced a duplication within the FVIII gene in a patient with mild hemophilia A.

We have characterized an unusual duplication of exon 13 within the factor VIII gene in a patient with a mild form of hemophilia A. This duplication was the result of a nonhomologous breakage and reunion event of two misaligned wild-type chromosomes. Sequence analysis of the breakpoint region revealed the presence of AT-rich sequences and possible topoisomerase I sites, whose involvement in several cases of illegitimate recombination has been postulated.

Effect of piribedil on plasma prolactin levels in women with puerperal or pathological hyperprolactinaemia.

In women with physiological puerperal hyperprolactinaemia, acute administration of Piribedil (100 mg po), a drug which stimulates dopamine receptor sites, was as effective as that of 2-Br-alpha-ergocryptine (CB 154, 5 mg po) in suppressing the elevated baseline plasma prolactin (PRL) levels. In two hyperprolactinaemic women with radiological evidence of an intrasellar pituitary tumour, Piribedil (100 mg po), in contrast to CB 154 (5 mg po), failed to modify plasma PRL levels, whereas in 3 other hyperprolactinaemic women with no radiological evidence of pituitary tumour, its effect was not clear-cut, even though it could not be differentiated from that of CB 154. These results indicate that Piribedil is an effective suppressor of plasma PRL levels in the human and suggest that its action is more evident in puerperal than in pathological hyperprolactinaemia.

A novel beta-globin structural mutant, Hb Brescia (beta 114 Leu-Pro), causing a severe beta-thalassemia intermedia phenotype.

This study describes a patient with a thalassemia intermedia-like phenotype in whom beta-globin gene sequencing detected a novel abnormal hemoglobin (Hb) due to a T-C substitution at codon 114 of the beta-globin gene arising as a de novo mutation. The abnormal variant was designated Hb Brescia after the place of birth of the propositus. Normal sequences were detected at the in trans beta-globin locus. In addition, alpha-globin gene analysis detected a triple alpha-globin locus which was inherited from the father. The T-C change at position 114 of the beta-globin gene results in a leucine to proline substitution (Leu-Pro) in the G-helix. The resulting Hb tetramer is highly unstable and precipitates forming inclusion bodies in the peripheral red blood cells. Moreover, the Leu-Pro substitution interferes negatively with the four alpha 1 beta 1 contact points of the G-helix most likely adversely affecting the alpha beta dimer formation. The very severe phenotype presented by our patient is unusual in a heterozygote for an unstable Hb variant and may be explained by the coinheritance of the triple alpha-globin locus.

A beta-thalassaemia phenotype not linked to the beta-globin cluster in an Italian family.

This paper describes a family of Central Italian origin in which three patients in two generations had either thalassaemia intermedia or a late presenting form of thalassaemia major. Sequence analysis of the patients' DNA revealed that only one of the beta-globin genes was affected by a beta-thalassaemia mutation (the codon 39 nonsense mutation), the other being completely normal, apart from the complex rearrangement (-T +ATA) at position -530 5' to the CAP site of the beta-globin gene, which has uncertain clinical significance. Haematologically, all these patients were characterized by unusually low HbF levels (1.8-7.3%) for a beta-thalassaemia major or intermedia phenotype. The mother of the two patients with thalassaemia intermedia was heterozygous for beta-thalassaemia (codon 39 nonsense mutation), while the father had thalassaemia-like red cell indices, an increased alpha/non alpha chain synthesis ratio, a slight increase of HbF and a low HbA2 level, but showed entirely normal beta-globin gene sequences, apart from the complex rearrangement (-T +ATA) at position -530 5' to the CAP site. One of the thalassaemia intermedia patients married a normal woman and they had a child with thalassaemia major who inherited only the codon 39 nonsense mutation but not the complex rearrangement at position -530. The clinical phenotype of thalassaemia-intermedia or major in the patients from this family may be explained by postulating the inheritance of the double heterozygous state for beta-thalassaemia and for a mutation in a gene coding for an erythroid-specific DNA binding protein which may impair the function of the normal beta-globin gene. Heterozygosity for this postulated mutation (father of the patients with thalassaemia intermedia) may result in the production of a beta-thalassaemia carrier state with normal HbA2 level.

Delta-thalassemia due to a mutation in an erythroid-specific binding protein sequence 3' to the delta-globin gene.

We have previously described a family of Northern Sardinian descent in which the propositus was affected by thalassemia major resulting from compound heterozygosity for codon 39 nonsense mutation and the beta +IVS II nt 745 mutation and in which all heterozygotes for the beta +IVS II nt 745 mutation had normal hemoglobin (Hb) A2 levels. To define the reasons for normal HbA2 levels in otherwise typical beta-thalassemia heterozygotes, we cloned and sequenced the delta-thalassemia gene in cis to the beta +IVS II nt 745 mutation. The sequence analysis showed a single nucleotide substitution (G----A) at position 69 nts (delta +69) downstream to the polyA addition site. Dot blot analysis with an oligonucleotide probe complementary to the delta +69 mutation detected this mutation in several heterozygotes for the beta +IVS II nt 745 mutation from the proband's family, but failed to show it either in a group of normal individuals of the same origin or in nonrelated heterozygotes for the beta +IVS II nt 745 mutation of the same or different descent from the proband. The delta +69 (G----A) mutation may be responsible for the low delta-globin output from the beta +IVS II nt 745 chromosome or could be a silent polymorphism not affecting the function of the delta-globin gene. The normal G at position 69 is part of a sequence very similar to the core DNA (A/T)GATA(A/G) motif (GATA box) that is a binding site for the GATA-1 protein. Gel-retardation assay has shown that a DNA fragment containing the GATA motif with the G----A at position +69 has increased binding affinity for erythroid-specific DNA binding protein(s) as compared with the wild-type sequence. These findings may suggest that the delta +69 mutation is responsible for the deficient function of the in cis delta-globin gene.

The C-T substitution in the distal CACCC box of the beta-globin gene promoter is a common cause of silent beta thalassaemia in the Italian population.

This paper describes four families of Italian descent in each of which the propositus had the clinical phenotype of thalassaemia intermedia, resulting from the compound heterozygous state for high HbA2 beta thalassaemia and type I silent beta thalassaemia. Direct sequencing on amplified DNA and/or oligonucleotide analysis detected, in all families but one, the compound heterozygous state for codon 39 nonsense mutation and the C-T substitution at position -101 in the distal CACCC box of the beta-globin gene promoter (beta th-101). Members of these families who are heterozygous for high HbA2 beta thalassaemia showed the codon 39 nonsense mutation, while those with the clinical phenotype of silent beta thalassaemia had the beta th-101 mutation. In the remaining family, the propositus and one of his siblings had the compound heterozygous state for a molecularly undefined high HbA2 beta thalassaemia and the beta th-101 mutation in combination with the triple alpha globin gene arrangement. These patients showed a more severe thalassaemia intermedia like clinical phenotype as compared to those with the same beta-globin genotype and a normal alpha-globin gene arrangement. In the families investigated the beta th-101 was always associated with haplotype I. A group of patients with thalassaemia intermedia from Southern Italy, either homozygous or heterozygous for haplotype I and in whom previous studies had failed to define the mutation in one of the beta thalassaemia globin genes, were screened by oligonucleotide analysis for the presence of the beta th-101. Three out of nine were positive. These results indicate that the beta th-101 mutation is a common cause of the type I silent beta thalassaemia phenotype in the Southern Italian population.

A DNA fragment from Xq21 replaces a deleted region containing the entire FVIII gene in a severe hemophilia A patient.

In this paper we report the molecular characterization of a large deletion that removes the entire Factor VIII gene in a severe hemophilia A patient. Accurate DNA analysis of the breakpoint region revealed that a large DNA fragment replaced the 300-kb one, which was removed by the deletion. Pulsed-field gel electrophoresis analysis revealed that the size of the inserted fragment is about 550 kb. In situ hybridization demonstrated that part of the inserted region normally maps to Xq21 and to the tip of the short arm of the Y chromosome (Yp). In our patient this locus is present both in Xq21 and in Xq28, in addition to the Yp, being thus duplicated in the X chromosome. Sequence analysis of the 3' breakpoint suggested that an illegitimate recombination is probably the cause of this complex rearrangement.

Promoter mutations producing mild beta-thalassaemia in the Italian population.

In this study we have investigated the molecular basis for a mild form of beta-thalassaemia in three patients of Italian descent. In two, belonging to different families and affected by a mild and late-presenting form of thalassaemia major, direct sequencing of amplified DNA detected a C----T substitution at position -87 of the beta-globin gene in the compound heterozygous state either with codon 39 nonsense mutation or beta +IVSI, nt 110 mutation. The -87 (C----T) mutation has been previously described, in combination with the beta +IVSI, nt 110 mutation, in a single patient with thalassaemia intermedia. Both our patients showed a more severe phenotype as compared to that resulting from compound heterozygosity for a severe beta-thalassaemia mutation and another promoter mutation (-87, C----G) at the same position. In the third patient with the thalassaemia intermedia phenotype, we detected a novel promoter mutation, consisting in a C----A substitution at position -86, in combination with the codon 39 nonsense mutation. The results of this study indicate that different nucleotide substitutions affecting the proximal CACCC box of the beta-globin gene in combination with severe beta-thalassaemia, produce a mild form of thalassaemia ranging in severity from thalassaemia intermedia to late-presenting thalassaemia major.

Recurrent mutations and three novel rearrangements in the factor VIII gene of hemophilia A patients of Italian descent.

Hemophilia A (HA), a common inherited bleeding disorder in humans, is due to the deficiency or absence of the factor VIII (FVIII) activity. The cloning of the FVIII gene has made molecular probes available for the characterization of the basic defect in this disease. In this study we describe six different mutations in the FVIII gene detected by DNA analysis of 100 HA patients of Italian descent. In two of them, with a severe clinical picture, we identified two novel deletions, one in the middle of the FVIII gene from exons 7 to 22 and the other encompassing the entire factor VIII gene. Both of these patients produced antibodies to factor VIII. In a patient with mild HA we detected a duplication of exon 13, which is a rearrangement not yet described within the FVIII gene. A possible explanation for the mild phenotype in this patient is that the molecular defect results in the production of an unstable FVIII protein with residual 10% FVIII activity. Screening by Taq I restriction endonuclease detected three mutations that were further characterized by direct sequencing on amplified DNA: a C-T substitution at codon 1960, in exon 18, converting the codon for arginine to a non-sense codon; and a G-A substitution at codon 2228 and 2326, in exons 24 and 26 respectively, resulting in the substitution of glutamine for arginine. All three of these mutations have been previously described. The non-sense mutation and the codon 2228 G-A mutation was found in patients with severe HA, while the codon 2326 G-A mutation was associated with a quite severe condition. These results confirm that the molecular bases of HA are very heterogeneous and provide further evidence that recurrent mutations are not uncommon in this system.